linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Ard Biesheuvel <ardb+git@google.com>
To: linux-kernel@vger.kernel.org
Cc: Ard Biesheuvel <ardb@kernel.org>,
	Kevin Loughlin <kevinloughlin@google.com>,
	 Tom Lendacky <thomas.lendacky@amd.com>,
	Dionna Glaze <dionnaglaze@google.com>,
	 Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	 Dave Hansen <dave.hansen@linux.intel.com>,
	Andy Lutomirski <luto@kernel.org>,  Arnd Bergmann <arnd@arndb.de>,
	Nathan Chancellor <nathan@kernel.org>,
	 Nick Desaulniers <ndesaulniers@google.com>,
	Justin Stitt <justinstitt@google.com>,
	 Kees Cook <keescook@chromium.org>,
	Brian Gerst <brgerst@gmail.com>,
	linux-arch@vger.kernel.org,  llvm@lists.linux.dev
Subject: [PATCH v5 02/16] x86/startup_64: Use RIP_REL_REF() to assign phys_base
Date: Wed, 21 Feb 2024 12:35:09 +0100	[thread overview]
Message-ID: <20240221113506.2565718-20-ardb+git@google.com> (raw)
In-Reply-To: <20240221113506.2565718-18-ardb+git@google.com>

From: Ard Biesheuvel <ardb@kernel.org>

phys_base is assigned from code that executes from a 1:1 mapping so it
cannot use a plain access from C. Replace the use of fixup_pointer()
with RIP_REL_REF(), which is better and simpler.

While at it, move the assignment to before the addition of the SME mask
so there is no need to subtract it again, and drop the unnecessary
addition (phys_base is statically initialized to 0x0)

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 arch/x86/kernel/head64.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 1d6865eafe6a..f98f5b6a06b5 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -192,6 +192,7 @@ unsigned long __head __startup_64(unsigned long physaddr,
 	 * and the address I am actually running at.
 	 */
 	load_delta = physaddr - (unsigned long)(_text - __START_KERNEL_map);
+	RIP_REL_REF(phys_base) = load_delta;
 
 	/* Is the address not 2M aligned? */
 	if (load_delta & ~PMD_MASK)
@@ -301,12 +302,6 @@ unsigned long __head __startup_64(unsigned long physaddr,
 	for (; i < PTRS_PER_PMD; i++)
 		pmd[i] &= ~_PAGE_PRESENT;
 
-	/*
-	 * Fixup phys_base - remove the memory encryption mask to obtain
-	 * the true physical address.
-	 */
-	*fixup_long(&phys_base, physaddr) += load_delta - sme_get_me_mask();
-
 	return sme_postprocess_startup(bp, pmd);
 }
 
-- 
2.44.0.rc0.258.g7320e95886-goog


  parent reply	other threads:[~2024-02-21 11:35 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-02-21 11:35 [PATCH v5 00/16] x86: Confine early 1:1 mapped startup code Ard Biesheuvel
2024-02-21 11:35 ` [PATCH v5 01/16] x86/startup_64: Simplify global variable accesses in GDT/IDT programming Ard Biesheuvel
2024-02-26 12:12   ` [tip: x86/boot] x86/boot/64: " tip-bot2 for Ard Biesheuvel
2024-02-21 11:35 ` Ard Biesheuvel [this message]
2024-02-26 12:12   ` [tip: x86/boot] x86/boot/64: Use RIP_REL_REF() to assign 'phys_base' tip-bot2 for Ard Biesheuvel
2024-02-21 11:35 ` [PATCH v5 03/16] x86/startup_64: Use RIP_REL_REF() to access early_dynamic_pgts[] Ard Biesheuvel
2024-02-26 12:12   ` [tip: x86/boot] x86/boot/64: " tip-bot2 for Ard Biesheuvel
2024-02-21 11:35 ` [PATCH v5 04/16] x86/startup_64: Use RIP_REL_REF() to access __supported_pte_mask Ard Biesheuvel
2024-02-26 12:12   ` [tip: x86/boot] x86/boot/64: Use RIP_REL_REF() to access '__supported_pte_mask' tip-bot2 for Ard Biesheuvel
2024-02-21 11:35 ` [PATCH v5 05/16] x86/startup_64: Use RIP_REL_REF() to access early page tables Ard Biesheuvel
2024-02-26 12:12   ` [tip: x86/boot] x86/boot/64: " tip-bot2 for Ard Biesheuvel
2024-02-21 11:35 ` [PATCH v5 06/16] x86/startup_64: Use RIP_REL_REF() to access early_top_pgt[] Ard Biesheuvel
2024-02-26 12:12   ` [tip: x86/boot] x86/boot/64: " tip-bot2 for Ard Biesheuvel
2024-02-21 11:35 ` [PATCH v5 07/16] x86/startup_64: Simplify CR4 handling in startup code Ard Biesheuvel
2024-02-21 14:52   ` Brian Gerst
2024-02-21 11:35 ` [PATCH v5 08/16] x86/startup_64: Defer assignment of 5-level paging global variables Ard Biesheuvel
2024-02-21 11:35 ` [PATCH v5 09/16] x86/startup_64: Simplify calculation of initial page table address Ard Biesheuvel
2024-02-21 11:35 ` [PATCH v5 10/16] x86/startup_64: Simplify virtual switch on primary boot Ard Biesheuvel
2024-02-23 13:11   ` Ard Biesheuvel
2024-02-21 11:35 ` [PATCH v5 11/16] x86/sme: Avoid SME/SVE related checks on non-SME/SVE platforms Ard Biesheuvel
2024-02-21 11:35 ` [PATCH v5 12/16] efi/libstub: Add generic support for parsing mem_encrypt= Ard Biesheuvel
2024-02-21 11:35 ` [PATCH v5 13/16] x86/boot: Move mem_encrypt= parsing to the decompressor Ard Biesheuvel
2024-02-21 11:35 ` [PATCH v5 14/16] x86/sme: Move early SME kernel encryption handling into .head.text Ard Biesheuvel
2024-02-21 11:35 ` [PATCH v5 15/16] x86/sev: Move early startup code into .head.text section Ard Biesheuvel
2024-02-21 11:35 ` [PATCH v5 16/16] x86/startup_64: Drop global variables keeping track of LA57 state Ard Biesheuvel

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20240221113506.2565718-20-ardb+git@google.com \
    --to=ardb+git@google.com \
    --cc=ardb@kernel.org \
    --cc=arnd@arndb.de \
    --cc=bp@alien8.de \
    --cc=brgerst@gmail.com \
    --cc=dave.hansen@linux.intel.com \
    --cc=dionnaglaze@google.com \
    --cc=justinstitt@google.com \
    --cc=keescook@chromium.org \
    --cc=kevinloughlin@google.com \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=llvm@lists.linux.dev \
    --cc=luto@kernel.org \
    --cc=mingo@redhat.com \
    --cc=nathan@kernel.org \
    --cc=ndesaulniers@google.com \
    --cc=tglx@linutronix.de \
    --cc=thomas.lendacky@amd.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).